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991.
Cotton fabrics were treated with Biopag, which does not have any functional groups that are reactive toward cellulose, using crosslinking agents or a binder, for the purpose of imparting a durable antimicrobial finish. In this respect, it was found that the crosslinking agents were more effective than the binder. It was confirmed by FT‐IR that the characteristic split peaks of Biopag were still seen even after repeated launderings. The crosslinking agents deteriorated the whiteness and tensile strength of the Biopag‐treated cotton fabrics, while the wrinkle recovery angles (WRAs) were significantly improved. The one‐step padding of Biopag and the crosslinking agent was found to be superior to the two‐step padding method in which Biopag padding was followed by padding of crosslinking agent in respect of WRA, whereas the whiteness and tensile strength were vice versa. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007  相似文献   
992.
The main objective of this study was to develop a method for systemic‐structural analysis and design of manufacturing assembly operations based on the activity theory. The “activity” was defined as behavior distinctively specific to workers, associated with mobilizations and realization of conscious manufacturing goals. The fundamental units of analysis of activity are actions that are both motor and mental. Activity is considered as a complicated structure of actions that are logically ordered in space and time. Each action is comprised of different operations. The building blocks of motor actions are motions. The building blocks of cognitive actions are mental operations. Activity integrates not merely cognitive and behavioral components, but the energy components as well. The proposed methodology is illustrated using an example of two manufacturing assembly operations. © 2001 John Wiley and Sons, Inc.  相似文献   
993.
The control of unexpectedly rapid Li intercalation reactions without structural instability in olivine‐type LiFePO4 nanocrystals is one of the notable scientific advances and new findings attained in materials physics and chemistry during the past decade. A variety of scientific studies and technological investigations have been carried out with LiFePO4 to elucidate the origins of many peculiar physical aspects as well as to develop more effective synthetic processing techniques for better electrochemical performances. Among the several features of LiFePO4 that have attracted much interest, in this article we address four important issues—regarding doping of aliovalent cations, distribution of Fe‐rich secondary metallic phases, nanoparticle formation during crystallization, and antisite Li/Fe partitioning—by means of straightforward atomic‐scale imaging and chemical probing. The direct observations in the present study provide significant insight into alternative efficient approaches to obtain conductive LiFePO4 nanocrystals with controlled defect structures.  相似文献   
994.
The effect that hydrostatic pressure has on the decomposition behavior in Cu54Ni6Zr22Ti18 bulk metallic glass (BMG) alloy was assessed using samples, which were isothermally annealed in the supercooled liquid region (SLR) with and without application of hydrostatic pressure. During subsequent annealing for the thermal analysis, the samples annealed under hydrostatic pressure displayed a slower crystallization process in the SLR, which is attributed to a retarded compositional decomposition of the BMG alloy under pressure.  相似文献   
995.
Safe and robust process design relies on knowledge of the evolution of the mechanical properties in a tube during hydroforming. The manufacturing of tubular shapes generally consists of three main stages: bending, preforming, and expansion. The latter is usually called hydroforming. As a result of these three steps, the final product’s strain hardening history is nonlinear. In the present study, the strain hardening behavior during hydroforming was experimentally investigated. The variation of local flow stress and/or local hardness was used as an index of the strain hardening during the various steps and the local flow stress and/or local hardness were used with respective correlations to determine the effective strain. The strain hardening behavior during hydroforming after preforming has been successfully analyzed by using the relationships between hardness, flow stress, and effective strain for variable pre-strains prior to hydroforming. The comparison of predicted hardness with measured hardness confirms that the methodology used in this study is feasible, and that the strain hardening behavior can be quantitatively estimated with good accuracy.  相似文献   
996.
For synchrotron X-ray micro-imaging of micro-scale biological flows in organisms, the development of a suitable flow-sensing tracer is essential for visualizing opaque flows quantitatively. In order to achieve this development in this study, the techniques employed in three different research fields were integrated namely, X-ray optics for enhancing X-ray concentration, fluid dynamics to satisfy the flow traceability and drug delivery system to fabricate bio-compatible microcapsules. On the front burner, we need a special sensor which can be well observed in X-ray micro-imaging and follow working fluid as well. As a result, bio-compatible micro-scale microcapsule sensors that perform the role of spherical micro lenses were developed. These novel microcapsules exhibit not only much improved contrast enhancement but also better performance as sensor tracers in micro-scale flows, compared to conventional solid particles.  相似文献   
997.
The esterification reaction of acrylic acid (AA) with 1,4‐butanediol (BD) to produce 4‐hydroxybutyl acrylate (HBA) was carried out in a batch reactive distillation mode over the Amberlyst 15 catalyst. The reactive distillation was highly desirable to increase the reaction rate of BD and eventually to obtain the high purity of HBA because the unreacted BD was not easily separable to the produced HBA after the reaction. The reaction pressure below 760 mm Hg was used to remove the by‐product water from the reaction zone. The air‐bubbling operation was successfully applied to prevent the polymerization of reactants and products under the vacuum condition (400 ~ 760 mm Hg). The reaction rates were strongly dependent on the reaction pressure, especially, the reaction rate of BD disappearance. The increased reaction rate of BD by the reactive distillation enabled to produce a high purity of HBA.  相似文献   
998.
Fine-sized BaMgAl10O17:Eu2+ phosphor powders with plate-like morphology were prepared by spray pyrolysis process. The effects of ratio of BaF2 and Ba(NO3)2 used as the source materials of Ba component on the morphological and optical properties of the BaMgAl10O17:Eu2+ phosphor powders were investigated. BaF2 was used as the flux material as well as the source material of Ba component. The phosphor powders prepared from the spray solution with the same mole concentrations of BaF2 and Ba(NO3)2 had fine size, plate-like morphology and narrow size distribution. The addition of BaF2 as the source material of Ba component increased the photoluminescence intensities of the phosphor powders. The phosphor powders prepared from the spray solution with the ratios of BaF2 and Ba(NO3)2 larger than 1 had the similar photoluminescence intensities to that of the commercial product.  相似文献   
999.
(–)‐Epigallocatechin gallate (EGCg) is the major component of green tea and is known to show strong biological activity, although it can be easily oxidized under physiological conditions. In this study, we indicate that EGCg is stable in human serum and that human serum albumin (HSA) stabilizes EGCg under aerobic condition. Although EGCg is usually decomposed within 1 h in aqueous solution at neutral pH, EGCg in serum and phosphate buffer (pH 7.4) containing HSA was stable over 1 h, even at neutral and slightly alkaline pH. Under these conditions, EGCg binds to HSA non‐covalently. The sulfhydryl group acts as an antioxidant for EGCg oxidation. Incubation of EGCg with HSA is accompanied by the oxidation of a free sulfhydryl group in HSA. These results suggest that the antioxidant property and the binding capacity of HSA contribute to the stabilization of EGCg in human serum.  相似文献   
1000.
Changes in projects are common and may be deleterious or beneficial—whether you see a change as a conflict or a valuable lesson depends only on your prospective. Project changes affect the cost, the scheduling, and the duration of projects, both directly and indirectly. Despite many articles and much discussion in practice and academic literature, there is a lack of information about systematic approaches to manage project change. This paper introduces a comprehensive project change management system that is founded on five principles: (1) promote a balanced change culture; (2) recognize change; (3) evaluate change; (4) implement change; and (5) continuously improve from lessons learned. By applying this project change management system, project participants can minimize deleterious change and promote beneficial change.  相似文献   
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